Software applications that run on mobile devices (any device that utilises a mobile operating system, such as a smartphone or tablet) are frequently described as apps. The APA 6th edition publication manual was published in 2010 and does not contain any referencing guidance or examples for apps. To reference an app in an academic work, use the following information.
In relationship to Smith (2017)...
As noted in the second app (Smith, 2017)...
Rightsholder, A. A. (year). Title of Software or Program (Version number) [Mobile application software]. Retrieved from http://xxxxx
Skyscape. (2013). Skyscape Medical Resources (Version 1.17.42) [Mobile application software]. Retrieved from http://itunes.apple.com
For more information, see the blog by Chelsea Lee on the APA Style blog.
Lee, C. (2013, 1 March 2013). How to cite a mobile app. APA Style Blog. Retrieved 28 May, 2019, from https://blog.apastyle.org/apastyle/2013/03/how-to-cite-a-mobile-app.html